SharePoint this field must be indexed to enforce unique values

This SharePoint tutorial, we will discuss how to solve an error This field must be indexed to enforce unique values that come while adding a content type to list in SharePoint Online/2013/2016.

Recently we have created a few site columns of type “Managed Metadata” in SharePoint, where we read the values from the SharePoint term store.

After that, we added those site columns to the content type. Then when we add those content types to any list the below error comes. The error message says: “This field must be indexed to enforce unique values”.

Edit the managed metadata site column and then change the “Enforce unique values: ” to Yes like below:

After this, we were able to attach content type to list.

You may like following SharePoint tutorials:

• Create an index in SharePoint Online list using CSOM
• SharePoint 2016/Online List View Auto Indexing Automatic Index Management
• How to create and remove the indexed column using PowerShell in SharePoint Online/2013/2016 list or document library?

This tutorial we learned, how to solve sharepoint this field must be indexed to enforce unique values error.